@inject ILogger<AsyncRenderOfSubComponentDuringInit> log
<Wrapper>
    @if (_eitherOr)
    {
        <Wrapper>
            <Simple1 Header="FIRST" />
        </Wrapper>
    }
    else
    {
        <Wrapper>
            <Simple1 Header="SECOND" />
        </Wrapper>
    }
</Wrapper>

@code
{
    private bool _eitherOr = true;

    [Parameter] public Task EitherOr { get; set; } = Task.CompletedTask;

    protected override async Task OnInitializedAsync()
    {
        log.LogDebug($"Before awaiting {nameof(EitherOr)}");
        await EitherOr;
        log.LogDebug($"After awaiting {nameof(EitherOr)}");
        _eitherOr = false;
    }
}
